Temperature compensating means for weighing scales



g- 1933- w. F. STIMPSON ET AL 1,921,343

TEMPERATURE GOMPENSATING MEANS FOR WEIGHING SCALES Original Filed Oct. 51, 1928 3 Sheets-Sheet l W2 3 (fer/7S tam 9 WZZZZJ Z7 fz'rzcb ATTORNEYS Aug. 8, 1933. w. F. STIMPSON ET AL TEMPERATURE COMPENSATING MEANS FOR WEIGHING SCALES Original Filed Oct. 51, 1928 3 Sheets- Sheet 2 INVENTORS BY jw 7 2/ ATTORNEYS g- 1933- w. F. STIMPSON El AL 1,921,348

TEMPERATURE COMPENSATING MEANS FOR WEIGHING SCALES Original Filed Oct. 31, 1928 3 Sheets-Sheet 3 ATTORNEY-S Patented Aug. 8, l933 PATENT OFFICE TEMPERATURE COMPENSATING MEANS FOB, WEIGHING SCALES 1 Walter F. Stimpson, Detroit, Mich, and Willis E. F1nch,'Bareville, Pa.; said Finch assignor to said Stimpson Continuation of application Serial No. 316,123,

October 31, 1928. This application August 7,

1931. Serial No. 555,690

12 Claims.

This invention relates to weighing scales, and more particularly to temperature compensating means therefor, and the present application is V a=continuation of our previously filed copend- 6 ing application, Serial No. 316,123, filed October .In scales employing springs as load-counterbalancing .means, the expansion and contraction of the springs which results from varying temperatures mustbe counteracted if the scale is -to remain accurate despite such expansion andcontraction. It is common to provide thermostatically controlled means for varying the eflecttve" length of one of the levers or some other portion of the mechanism for this pur-' pose. One trouble frequently arising inconnection with the application of such an arrangement to this purpose is the. difficulty in positively locking the thermostatically controlled elements in a manner to prevent movement th'ereofunder any otherinfluenee than that of changing temperature; Since of necessity the pertsmust :be freely movable when actuated by the thermostat under normal conditions, the

' load placed on the scale platform 'is apt to cause undesired movement of these parts unless positive locking means is provided. It is an object of our invention to provide such a positive locking means which will be very simple and effective in operation, and will not interfere with the freedom of operation of the thermostat when no load, or only a. relatively light load, is on the platform of the scale, but which will absolutely prevent undesired movement of the'thermostat and the elements controlled by it, no matter whatload, within the capacity of the scale, may

be placed upon the platform. 5

Another object of this invention is the promy vision of an improved, nose iron construction which will be of simple and efficient construction. and easily controllable by the thermostat to neutrali ze expansionand contraction of the load-counterbalancing element.

I Other objects and advantages will be apparent from the following description, whereinreferance is made to the accompanying drawings illustrating preferred embodiments of our inven- 1 tion, and wherein similar reference numerals V designate'similar parts. throughout the several In the drawings:

, Figural isa plan view of-the lower portion of such a scale embodying QurinVention, with thecover and platform-supporting levers and pivots, thermostat and other members housed by the base of the scale. Figure 2 is a detail longitudinal sectionalview' taken substantially on the line 2f-2 of Figure- 1, looking in the direction of the arrows.

Figure 3 is a fragmentary detail plan view of the form of our invention shown in Figure 2 and, the portions of the scale mechanism with which it is associated, part of the nose iron channel being broken away to afford a better view of. the nose iron.

Figure 4 is a detail sectional view taken stantially on the line 4-4 of Figure 2.

Figure 5 is a view similar to Figure2 of a modified form of our invention, the parts being shown in the positions they assume when a suflicient load is upon the scale platform to' actuate the locking means.

Figure 6 is a fragmentary side view, partly in elevation and partly in section, of a scale em bodying this modified form of our improved thermostat and nose iron construction. 7

Figure '7 is a detail sectional view similar to Figure 5 but showing the positioning of the various parts when no load is on the platform, or a load which is insufficient to actuate the locking means.

Figure 8 is an enlarged detail plan view of the modified embodiment of our invention and the scale members to. which it is applied. 1 Figure 9 is a detail sectional view taken substantially on the line 9-9 of Figure 8.

Figures 10 and 11 are detail perspective views of the locking construction employed in the modified form of our invention to prevent undesired movement of the thermostatically controlled elements.

Referring now to the drawings: The scale constructions here shown are of a well-known form commonly employed with scales of the cylinder type, although the cylinder portions are 'not shown; and it will be apparent that our invention is easily adaptable to other classes of scales.-

Upon the platform 10 are placed objects desired to be weighed. A lever system (which forms no part of this invention) is actuated by the platform, and through the. lever 11 move- .ment is transmitted to the load-counterbalancing means and to the indicator. .No showing of the indicator actuating means is included, as it forms no part of this. invention and would unnecessarilygcomplicate the drawings- The load- "counterbalancing means may comprise one or" upper of v1mm tn lever pydangeroua dude" w the mo .A W I mpqlmhmtxot weproviouala g; with 13 .4 ham-beg;

with

opposite and from that' can'yinx ,gr 13'.1n the cal-deg u'pqn its bottom 6; 1, arm-n. Secured tothe u mas side rammar angularity of the lever 11, and consequently the ,angularity of the pull upon thenose iron throughthe knife edge pivot l61'1, might result in longitudinal shifting of the nose iron, this undesirable result is effectively prevented by the engagement 'oi the notched plates. The

serrations are preferably relatively fine,

so that they cannot materially disturb the longitudinal relationbetween the nose iron and the lever when for ed together.

While it wi fie apparent that the illustrated embodiments of our invention herein disclosed are well calculated toadequately fulfill the ob jects and advantages primarily stated, it is to be understood that the invention is susceptible to variatiommcdification and change, within the spirit and scope of the subjoined claims.

What we claim is:

1. In a weighing scale having load support- "ing means, a lever movable proportionately to the load carried thereby, and load counterbalancing means variable in effective resistance to the load with changes of temperature, means for counteracting such variances of the load counterbalancing means, comprising a slidable portion carried by the lever, a thermostat for controlling the sliding thereof proportionately to temperature variances, and means for locking the slidable portion against such movement when sufficient load is placed upon the scale.

2. In a wei hing scale incorporating load supporting means, a lever movable in response to the placing of 'a load thereon, and load counterbalancing means expansible and contractable with variances of temperature, means for neutralizing the eifect of such expansion and contraction, comprising a slidable extension carried by the lever, a thermostat controlling the sliding thereof, and means for locking the extension against such slidable movement when the load upon the scale reaches a predetermined point.

3. In a weighing scale incorporating load supporting means, a lever movable in response and proportionately to the load placed thereon, and load counterbalancing means variable in efficiency with variances of temperature, means for neutralizing such variances of efliciency, comprising a thermostat, an eilective portion -carried by the lever capable of limited independent movement, movable in one direction under control of the thermostat, and proportionately movable in another direction in re- Sponse to the load placed upon the scale, and

means for preventing the thermostat-controlled movement of said portion of the lever when its load-induced movement has attained a predetermined travel.

4.- In a weighing scale incorporating load supporting means, a lever movable in response to the load placed thereon, and load counterbalancing means variable in efiiciency with variances of temperature, means for neutralizing such variances of eflicienoy, comprising a ;thermostat,, a quasi-independent section carplaced upon the scale, and means for preventing movement in the first mentioned line of travel when the transverse movement has reached a predetermined point.

5. In a weighing scale having load supporting means, a lever movable in response and proportionately to the load placed thereon, and load counterbalancing means variable in efficiency with variances of temperature,'means for neutralizing such variances of efficiency, comprising a thermostat, an extension carried by the lever longitudinally slidable by the thermostat to compensate for such temperature variances, and transversely movable in another direction in response to the load placed upon the scale, and means for locking the extension against movement in the first mentioned direction when the transverse movement has reached a predetermined point.

6. In a scale, a lever, a thermostat mounted thereon, an elongated guide member secured upon the lever at a distance from its fulcrum pivot, a pivot carrying a nose iron and a roller adjacent its forward extremity movable within the guide member and of greater diameter than the thickness of the nose iron, whereby the rear extremity of the nose iron slants downwardly into contact with the guide member whenever a sufficient pull is exerted upon the nose iron pivot, and a connection between the nose iron and thermostat.

'7. In a scale, a lever, a thermostat mounted thereon, an elongated guide member secured; upon the lever at a distance from its fulcrum pivot, a pivot carrying a nose iron and a pair of rollers at the sides of the nose iron adjacent its forward extremity movable within the guide member and of greater diameter than the thickness of the nose iron, whereby the rear extremity of the nose iron slants downwardly into contact with the guide member whenever sufiicient pull is exerted upon the nose iron pivot, and a connection between the nose iron and thermostat.

8. In a scale, a lever, a thermostat mounted thereon, an elongated guide member secured upon the lever at a distance from its fulcrum pivot, a pivot carrying a nose iron and a roller adjacent its forward extremity movable within the guide member and of greater diameter than the thickness of the nose iron, whereby the rear extremity of the nose iron slants downwardly into contact with the guide member whenever a suificient pull is exerted upon the nose iron pivot, a connection between the nose iron and thermostat, and locking means for the nose iron operable upon such contact between its rear extremity and the guide member.

9. In a scale, a lever, a thermostat mounted thereon, an elongated guide member secured upon the lever at a distance from its fulcrum stat, and locking members carried by the rear extremity of the nose iron and the adjacent portion of the guide member, engageable when contact is established between them by such a suilicient pull upon the nose iron pivot. 

